1. Field of the Invention
This invention relates to a pad for frictionally gripping lapping foils and polishing pads during the grinding, lapping and polishing of optical lenses made either of glass or transparent synthetic plastics material.
2. The Prior Art
Optical lenses are generally ground, lapped or polished by means of a tool having a carefully machined surface which conforms to that desired on one face of an optical lens. Sometimes the same tool has two such surfaces--one for shaping one side of the lens and the other for shaping the other side of the lens, or else one for producing an approximate surface on the lens and the other for producing an accurate surface on the lens. Usually the working surface or surfaces on these tools are of convex or concave shape.
In order to reduce the rate of wear on the said working surfaces of these tools, it is usual to apply to them an adhesive-backed replaceable pad which is sufficiently thin to be brought into conformity with the convex or concave working surface of the tool. Various forms of pad have been proposed in the past, including aluminium pads, steel pads and pads made of perforated metal so that slurry can be retained in the perforations.